2-D Structure of the A Region of Xist RNA and Its Implication for PRC2 Association
In model 1, the various stem-loop structures all involve two successive repeats. The repeats are indicated by red lines and are numbered from 1 to 8. Representations of chemical and enzymatic data are as in Figure 2. In each of the three panels, segments in which DMS and/or CMCT modifications were identified are indicated on a schematic drawing of the 2-D structure (full and dot lines for DMS and CMCT, respectively). In segments analyzed by the two chemical reagents, unmodified nucleotides are squared. However, one should take into consideration the fact that G residues are poorly modified by CMCT in the mild conditions that we used. The free energies of each stem-loop structures at 0°C and in 3 M NaCl were calculated with the M-fold software.